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Posavad CM, Koelle DM, Shaughnessy MF, Corey L.Posavad CM, et al. Among authors: koelle dm.Proc Natl Acad Sci U S A. 1997 Sep 16;94(19):10289-94. doi: 10.1073/pnas.94.19.10289.Proc Natl Acad Sci U S A. 1997.PMID: 9294203Free PMC article.